(例句] He has been warned of danger of driving after drinking wine.他已被提醒过酒后开车危险。

(例句] l shouted to him to warn him of the danger.

我大声叫他警告他有危险。

[例句] They warned him against swimming in that river .

他们警告他不要到那个河里游泳。

[例句] The doctor warned the patient against smoking.

医生告诫病人不要抽烟。